<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        * {
            margin: 0px;
            padding: 0px;
            list-style: none;
        }

        .f {
            width: 700px;
            /* border: 1px solid rebeccapurple; */
            margin: 20px auto;
        }

        ul {
            overflow: hidden;
        }

        ul li {
            float: left;
            margin-left: 20px;
            width: 65px;
            height: 30px;
            line-height: 30px;
            text-align: center;
        }

        .first{
            background-color: red;
            color: white;
            border-radius: 30px;
           
        }
    </style>

</head>

<body>
    <div class="f">
        <ul>
            <li class="first">全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>全部</li>
            <li>黑色电影</li>
            <li>全部</li>
            <li>古装</li>
            <li>全部</li>
            <li>黑色电影</li>
            <li>全部</li>
        </ul>
    </div>
</body>

</html>